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过渡金属的络合物被广泛用做催化剂,这是因为它们具有未被占有的d-轨道。从理论上推测,一个原子中能成键的轨道越多,它便有起更多反应的可能性。过渡金属只有5个d-轨道,而锕系和镧系金属则有7个f-轨道,应该有可能催化更多的反应。近年来,美国许多大学竞相开展锕系和镧系金属和有机配位体形成的络合物的研究。理论计算和实验结果都表明它们具有特殊的性能,并可能有很大的实用价值,特别是用于催化。例如氯化双五甲环戊二烯基铀[Bis(Penta-methylcyclopentadienyl)Uranium monochloride]是乙烯聚合的有效催化剂,二甲基双五甲环戊二烯基铀和二
Transition metal complexes are widely used as catalysts because they have unoccupied d-orbitals. In theory, it is hypothesized that the more orbits a bond can form in an atom, the more reaction it may have. Transition metals have only 5 d-orbitals, whereas actinides and lanthanides have 7 f-orbitals and should probably catalyze more reactions. In recent years, many universities in the United States compete to study the formation of complexes of actinides and lanthanides with organic ligands. Both theoretical calculations and experimental results show that they have special properties and may have great practical value, especially for catalysis. For example, Bis (Penta-methylcyclopentadienyl) Uranium monochloride is an effective catalyst for the polymerization of ethylene. Dimethyltetramethylcyclopentadienyl uranium and bis